Parameters

Return Values

User Contributed Notes 2 notes

I have looked at the code available in the Math package for percentile. I compared the result obtained with percentile from Excel and found that it doesnt match. So i wrote my own percentile function and verified the result with the Excel's percentile.

For those of you who need the percentile calculation of Excel in php..

If you are looking to infer the percentile from a z-score, you can use this function.
It's far from precise but does the job on most circumstances.
The error function ( erf() )is based on the approximation on wikipedia:
http://en.wikipedia.org/wiki/Error_function